At which stage of the new product development process is a physical product first developed?

 Product development

Explanation:

Product development is referred to as or known as the creation of the products and commodity with the different or new characteristics which further offer the additional or new benefits to their consumers or customer.  The product development also tends to involve several modification of the existing commodity or product and also its presentation, or the formulation of the entirely newer product which thus satisfies the newly defined consumer or customer want.

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